This invention relates generally to transmissions, more particularly to infinitely variable transmissions, and specifically to infinitely variable transmissions requiring no external controls and to power trains and systems which utilize such infinitely variable transmissions.
In the field of transmissions, a need has arisen for a transmission allowing the ratio between the input and output shafts to infinitely vary according to the rotational speed of the input shaft and the load on the output shaft. Further, such an infinitely variable transmission should allow the automatic selection of its own ratio in its range, based upon the input power, output load, and gear frictional resistance, and without the use of external members such as gear shifting members and the like. Additionally, such an infinitely variable transmission should have little power drag when the transmission is in direct drive.
Further a need has arisen for power trains utilizing such an infinitely variable transmission to power a varying rotational load through an infinite speed range in a smooth and stepless manner. Additionally, this speed control should be accomplished without excessive loads being placed on the power unit, so that an optimum speed ratio is maintained in spite of continuously varying load factors, but without requiring the use of any gear shifting members to control the ratio of the infinitely variable transmission. Still further this power train should have a high power to weight ratio, be mechanically efficient, be able to provide a dynamic braking effect, and be simple to manufacture and service.
Further, a need has arisen for a power source utilized within such a powertrain which is fuel efficient, mechanically efficient, produces few harmful exhaust emissions, is simple to manufacture and service, and has a high power to weight ratio.